Laboratory sample distribution system and corresponding method of operation

ABSTRACT

A laboratory sample distribution system is presented. The laboratory sample distribution system comprises a number of container carriers. The container carriers each comprise at least one magnetically active device such as, for example, at least one permanent magnet, and carry a sample container. The system further comprises a transport plane to carry the container carriers and a number of electro-magnetic actuators being stationary arranged below the transport plane. The electro-magnetic actuators move a container carrier on top of the transport plane by applying a magnetic force to the container carrier.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of PCT/EP2012/071762, filed Nov. 2,2012, which is based on and claims priority to EP 11187977.1, filed Nov.4, 2011, which are hereby incorporated by reference.

BACKGROUND

The present disclosure generally relates to a laboratory sampledistribution system and a corresponding method of operation.

Laboratory sample distribution systems are used to distribute samples orspecimens, for example, blood samples or specimens, between variousdifferent laboratory stations or specimen-processing instruments, suchas pre-analytical stations, analytical stations and post-analyticalstations.

In one prior art system, a drive mechanism which operates to advancespecimen-container racks on a surface by producing an X/Y movablemagnetic field below the surface. The movable magnetic field is producedby permanent magnets carried by an X/Y movable magnetic truck assembly.The magnetic field produced by each magnet magnetically couples withmagnetically-attractive members carried in a base portion of eachspecimen-transport rack. The magnetic bond between the magnets andmagnetically-attractive members is sufficiently strong that, as themagnetic truck assembly moves in the X/Y plane, a magnetically-coupledrack follows. Due to mechanical constraints caused by the X/Y movablemagnetic truck assembly independent simultaneous movements of multiplespecimen-transport racks are difficult to implement. Further,specimen-containers can only be moved together in specimen-transportrack quantities.

Therefore, there is a need to provide a laboratory sample distributionsystem and a corresponding method of operation that is highly flexibleand offers a high transport performance.

SUMMARY

According to the present disclosure, a laboratory sample distributionsystem is presented. The system comprises a plurality of containercarriers. Each container carrier can comprise at least one magneticallyactive device and can carry a sample container. The system can furthercomprise a transport plane to carry the container carriers and aplurality of electro-magnetic actuators stationary arranged below thetransport plane. The electro-magnetic actuators can move a containercarrier on top of the transport plane by applying a magnetic force tothe container carrier.

Accordingly, it is a feature of the embodiments of the presentdisclosure to provide a laboratory sample distribution system and acorresponding method of operation that is highly flexible and offers ahigh transport performance. Other features of the embodiments of thepresent disclosure will be apparent in light of the description of thedisclosure embodied herein.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

The following detailed description of specific embodiments of thepresent disclosure can be best understood when read in conjunction withthe following drawings, where like structure is indicated with likereference numerals and in which:

FIG. 1 illustrates a laboratory sample distribution system having atransport plane formed by multiple sub planes according to an embodimentof the present disclosure.

FIG. 2 illustrates a top view of an exemplary sub plane shown in FIG. 1according to an embodiment of the present disclosure.

FIG. 3 illustrates a detailed perspective side view of the sub planeshown in FIG. 2 according to an embodiment of the present disclosure.

FIG. 4 illustrates a container carrier according to a first embodimentof the present disclosure.

FIG. 5 illustrates a container carrier and a correspondingelectro-magnetic actuator according to a second embodiment of thepresent disclosure.

FIG. 6 illustrates a simulated magnetic flux density for a containercarrier positioned on top of an electro-magnetic actuator not activatedand an adjacent electro-magnetic actuator activated according to anembodiment of the present disclosure.

FIG. 7 illustrates a side view of an embodiment of a sub planecomprising a magnetizable coupling element providing a magnetic couplingbetween adjacent electro-magnetic actuators according to an embodimentof the present disclosure.

FIG. 8 illustrates movement of a container carrier and an activationorder of corresponding electro-magnetic actuators according to a firstembodiment of the present disclosure.

FIG. 9 illustrates movement of a container carrier and an activationorder of corresponding electro-magnetic actuators according to a secondembodiment of the present disclosure.

FIG. 10 illustrates a sub plane according to a further embodiment of thepresent disclosure.

DETAILED DESCRIPTION

In the following detailed description of the embodiments, reference ismade to the accompanying drawings that form a part hereof, and in whichare shown by way of illustration, and not by way of limitation, specificembodiments in which the disclosure may be practiced. It is to beunderstood that other embodiments may be utilized and that logical,mechanical and electrical changes may be made without departing from thespirit and scope of the present disclosure.

A laboratory sample or specimen distribution system according to a firstembodiment can comprise a plurality of container carriers such as, forexample about 50 to about 500 container carriers. The container carrierscannot be self-powered. The container carriers can comprise at least onemagnetically active, i.e. magnetically attractive, device and can carrya single sample container. Further, the system can comprise a twodimensional transport plane or supporting surface, which may becompletely planar and can carry at least part of the container carriers.A number of electro-magnetic actuators such as, for example about 50 toabout 5000 electro-magnetic actuators, can be arranged stationary orfixed below the transport plane. The electro-magnetic actuators can movea container carrier on top of the transport plane in at least twodifferent directions by applying or causing a magnetic force to thecontainer carrier, i.e. to the magnetically active device of thecontainer carrier.

The transport plane can support the container carriers in a way to allowmovement along directions as guided by magnetic forces. Accordingly, thetransport plane can be continuous in at least those directions ofmovements to allow a smooth travel of the container carriers. In orderto allow a flexible transfer of carriers along many lateral directions,a flat transport plane can be an advantage. On a microscopic level, itcan be advantageous to employ a surface with many small protrusions inorder to reduce friction between the transport plane and the bottomsurface of the container carrier.

The transport plane can further transmit the magnetic field of theelectro-magnetic actuators. Accordingly, the transport plane can be madefrom magnetically transmissive materials such as, for example, glass orplastics. Further, the thickness of the transport plane can be acompromise between mechanical stability and magnetic shielding. Atransport plane having a thickness of about 2 to about 10 mm can be wellsuited.

The magnetically active device can be a device to cause magnetic forcesin interaction with a corresponding magnetic field. The magneticallyactive device may comprise at least one permanent magnet. By themultiple electro-magnetic actuators interacting individually withcorresponding container carriers, it can be possible to independentlyand simultaneously move multiple individual sample containers along agiven grid over the transport plane offering high transport flexibility,which can mean that single containers can be transported independentlyfrom each other to desired locations on the transport plane.

The transport plane may be formed of multiple adjacent sub-planes. Thesystem may comprise a cover profile covering the transport plane, i.e.covering the sub-planes forming the transport plane. The cover profilecan simplify the cleaning of the transport plane and can avoiddisturbing gaps between adjacent sub-planes. Further, the cover profilecan mitigate height differences between adjacent sub-planes. The coverprofile may be fluidtight. The cover profile may be just overlying thetransport plane or may be glued to the top surface of the sub-planes tostabilize the arrangement and to prevent spacing which can reducemagnetic forces.

The cover profile may be a glass plate, a non-magnetic metal plate suchas, for example, an aluminum plate, or a foil of plastic material suchas, for example, a foil of polyethylene or PTFE(poly-tetra-fluoro-ethylene). A glass plate can be chemically resistant,easily washable and stiff, so that height differences between sub-planesmay be mitigated. For flexible cover profiles, a suitable thickness ofthe cover profile can be a compromise between mechanical stability,height mitigation and magnetic shielding. In the case of plasticmaterials, a cover profile having a thickness of about 1 to about 10 mmcan be well suited.

The surface of the container carriers and the surface of the transportplane, i.e. the surface of the cover profile, may be arranged to reducefriction between the surfaces, for example, by coating the containercarriers and/or the transport plane or cover profile and/or byroughening the contact surfaces of the container carriers and/or of thecover profile.

The electro-magnetic actuators may be arranged in rows and columnsforming a grid having a given, for example, constant, grid dimension.The grid dimension can specify a distance between adjacent orconsecutive electro-magnetic actuators in a given row or column.

The container carriers may have a stand. The stand may have a circularcross section having a diameter that is equal to or less than the griddimension. This dimensioning can make it possible that two carriersmoving on direct adjacent rows or columns formed by electro-magneticactuators can pass by each other without collision.

The electro-magnetic actuators may be arranged in rows and columnsforming a grid or matrix. Adjacent rows may have different griddimensions selected either from a first grid dimension or a second griddimension and adjacent columns may have different grid dimensionsselected either from the first grid dimension or the second griddimension, wherein the second grid dimension is larger, for example,twice as large, as the first grid dimension.

The container carriers each can have a stand. The stand can have acircular cross section having a diameter that can be equal to or lessthan the larger grid dimension.

The circular cross section of the stand can reduce the likelihood of astand collision of container carriers moving adjacent in differentdirections. Compared, for example, with quadratic stands, this canreduce the required safety distance between adjacent positions and therequirements on positioning accuracy. Further, the circular stand canimprove the self-supporting of the container carrier, for example, canprevent that the containers carrier tilts under normal operatingconditions.

The dimensioning of the size or diameter of the stand smaller than orequal to the larger grid dimension (i.e. the distance between theelectro-magnetic actuators forming the larger grid), wherein the largergrid dimension can be twice as large as the first grid dimension, canmake it possible that two carriers moving on adjacent tracks formed byelectro-magnetic actuators arranged according to the smaller griddimension can pass by each other without collision. On the other hand,the footprint can be large enough to provide a smooth transport withoutmuch tilting.

The electro-magnetic actuators may be arranged in rows and columnsforming a grid or matrix of active transport fields. The rows andcolumns can have either a first grid dimension g1 or a second griddimension g2, wherein g2=2*g1. Adjacent rows and adjacent columns canhave different grid dimensions. The grid dimension can specify adistance between adjacent or consecutive electro-magnetic actuators in agiven row or column. In other words, the electro-magnetic actuators canbe arranged in the form of a grid or matrix, wherein the grid or matrixcan have blank positions representing omitted electro-magneticactuators. This arrangement can consider that diagonal movements of thecontainer carriers may not be necessary to reach a specific destinationon the transport plane, since the specific destination can be reachedbased on movements along the rows and columns. This arrangement of theelectro-magnetic actuators can reduce the number of requiredelectro-magnetic actuators significantly (by, for example, 33%) comparedto a solution having a constant grid dimension. Nevertheless, if adiagonal movement is required, it can be self-evident that the rows andcolumns may be provided having a constant grid dimension, for example,forming a transport plane being divided in active transport fields withequal dimensions.

If the transport plane is divided into multiple sub-planes, eachsub-plane may have a first outer face, a second outer face, a thirdouter face and a fourth outer face at which further planes can bearranged in a tiling manner to form a transport plane. This approach canoffer the ability to provide transport planes of desired shape. This canbe a big advantage to serve the needs an individual laboratory mighthave due to the laboratory stations present or due to spatialrestraints.

The approach to build the transport plane from sub-planes can becombined with the concept of rows having different grid dimensions toreduce the number of needed electro-magnetic actuators. Sub-planes canbe employed where along the first and the second outer face theelectro-magnetic actuators can be arranged in a first grid dimension g1and along the third and the fourth outer face the electro-magneticactuators can be arranged in a second grid dimension g2, whereing2=2*g1. Multiple sub-planes can be arranged adjacent in a tiling mannerto form the transport plane, wherein adjacent outer faces of differentsub-planes have different grid dimensions.

The container carriers each may have a stand. The stand can have acircular cross section covering approximately five electro-magneticactuators if positioned in the center of a cross formed by fiveelectro-magnetic actuators. The electro-magnetic actuator in the centerof the cross may be fully covered wherein the four outerelectro-magnetic actuators may be covered by half if the stand ispositioned in the center of the cross formed by the fiveelectro-magnetic actuators. The stand may have a diameter in the rangeof about 3.5 cm to about 4.5 cm.

The ratio between the size or diameter of the stand relative to thedistance between the electro-magnetic actuators can make it possiblethat two carriers moving on adjacent tracks can pass by each otherwithout collision. On the other hand, the footprint can be large enoughto provide a smooth transport without much tilting.

Each electro-magnetic actuator may comprise a ferromagnetic core. Theferromagnetic core can cause a holding force acting on the at least onemagnetically active device of a container carrier placed on top of theelectro-magnetic actuator if the electro-magnetic actuator is not drivenby an actuating current.

The at least one permanent magnet may be ball-shaped, wherein a northpole or a south pole of the ball-shaped permanent magnet can be directedto the transport plane. In other words, an axis extending through theopposite poles of the ball-shaped permanent magnet can be perpendicularto the transport plane. A diameter of the ball-shaped permanent magnetmay be approximately 12 mm. The ball-shaped permanent magnet can causean optimized magnetic field in interaction with the electro-magneticactuators, e.g. compared with a bar magnet, resulting in higher magneticforce components in a lateral movement direction.

The permanent magnet in conjunction with a ferromagnetic core of acurrently adjacent non-activated electro-magnetic actuator can cause anunwanted magnetic retention force. The retention force can hinder thedesired movement of the container carrier away from the currentlyadjacent non activated electro-magnetic actuator towards an activatedelectro-magnetic actuator. Increasing the distance between the permanentmagnet and the transport plane, i.e. also increasing the distancebetween the permanent magnet and the electro-magnetic actuators, canreduce this magnetic retention force. Unfavorably, an increasingdistance can also lower a desired magnetic transport force in a lateralmovement direction. Therefore, a distance between a center of the atleast one permanent magnet and a bottom surface of the containercarrier, the bottom surface in contact with the transport plane, may beselected within a range of about 5 mm to about 50 mm. The given distancerange can provide an optimized compromise between a desired magnetictransport force in movement direction and an unwanted magnetic retentionforce.

The container carriers may comprise a first permanent magnet arranged inthe center of a stand of the container carrier and a second permanentmagnet having a ring shape arranged in the stand surrounding the firstpermanent magnet. This arrangement can provide high flexibility incausing push and pull magnetic forces, especially if more than oneelectro-magnetic actuator is activated at a given time. The first andsecond permanent magnets may have a reverse polarity, i.e. a south poleof the first permanent magnet and a north pole of the second permanentmay point to the transport plane, or vice versa. The ring shaped secondpermanent magnet may constitute a circular area having a diameter thatcan be smaller than a distance between axes of electro-magneticactuators of the transport plane.

The container carriers may comprise a RFID tag storing a unique ID. Thiscan enable matching a sample container ID, e.g. a barcode, with thecorresponding container carrier. The unique carrier ID can be read by anoptional RFID reader being part of the system and being placed at one ormore specific locations within the system.

The RFID tag may comprise a ring shaped antenna arranged in a stand ofthe container carrier. This antenna arrangement can make it possible toread the RFID tag by a RFID reader antenna below the transport plane.Thus, the transport plane itself and/or areas above the transport planemay be designed free of any disturbing RFID reader antennas.

The electro-magnetic actuators may comprise a ferromagnetic core guidingand amplifying a magnetic field. The electro-magnetic actuators may havea center finger and four outer fingers, each of the fingers extendingperpendicular to the transport plane. Only the center finger may besurrounded by a coil driven by an actuating current. This arrangementcan reduce the number of coils needed for activating theelectro-magnetic actuators, wherein the center finger and the outerfingers can interact advantageously by providing push and pull forces,respectively, especially if the container carrier comprises a firstpermanent magnet arranged in the center of the stand and a secondpermanent magnet having a ring shape arranged in the stand surroundingthe first permanent magnet.

The system may further comprise a container carrier sensing device tosense the presence and position of container carriers located on thetransport plane. The container carrier sensing device can provide for anoptimized tracking of container carriers placed on top of the transportplane.

The container carrier sensing device may be embodied based on infra-red(IR) based reflection light barriers. These light barriers may bearranged in recesses in the transport plane or may be arranged below atransport plane which can be at least partially transparent for theemployed light. In the latter case, a closed transport plane can beprovided which inter alia can be easier to clean.

The system may comprise a magnetizable coupling element to provide amagnetic coupling between adjacent electro-magnetic actuators. Due tothe coupling element, the activated electro-magnetic actuator canautomatically cause a magnetic field in the adjacent actuators having aninverse polarization. This can automatically provide respective pull andpush forces even if only a single electro-magnetic actuator isactivated, e.g. by a corresponding activating current.

The system may comprise a security cover to cover the transport planeand the container carriers placed on the transport plane. The securitycover can cover the transport plane and the container carriers placed onthe transport plane such that the container carriers can move unhinderedover the transport plane. The security cover may e.g. be made oftransparent plastic. The security cover can prevent contamination andunintentional access to the transport plane. The security cover may havea footprint which can be approximately equal to the footprint of thetransport plane.

The security cover may have an open state and a closed state, wherein inthe open state, the transport plane or dedicated areas of the transportplane may be accessible by a user and in the closed state, the transportplane may not be accessible by a user, thereby preventing damage and/ormanual access causing unwanted positions of container carriers placed onthe transport plane. The security cover may have flaps or sectionsoperable such that specific sections/areas on the transport plane can beaccessible. The security cover can further prevent pollution of thetransport plane.

A method for the versatile transport of sample containers can beachieved with a laboratory sample distribution system comprising anumber of container carriers as described above. The container carrierscan comprise at least one magnetically active device and can carry asample container. The laboratory sample distribution system can furthercomprise a transport plane to carry the container carriers and a numberof electro-magnetic actuators being stationary arranged below thetransport plane. The electro-magnetic actuators can move a containercarrier on top of the transport plane by applying a magnetic force tothe container carrier. The method can comprise activating at least oneof the electro-magnetic actuators to apply a magnetic force to acontainer carrier within an operating distance of the at least oneactivated electro-magnetic actuator. Activating an electro-magneticactuator can mean that a magnetic field can be generated by theelectro-magnetic actuator. Activating may be done by generating adriving current applied to a coil surrounding a ferromagnetic core.

The speed of a container carrier moving across the transport plane maybe set by setting a period between a successive activation of adjacentelectro-magnetic actuators. If this duration is set shorter, the speedcan increase and vice versa. By changing the duration dynamically, acontainer carrier may be accelerated or slowed down.

The electro-magnetic actuators may be activated in response to a sensedposition of the container carrier to be applied with the magnetic force.The electro-magnetic actuators may be activated such that a polarity ofthe generated magnetic field can depend on a position of the containercarrier relative to the electro-magnetic actuator. This can causeposition-depended pull and push forces. In a first position range whenthe container carrier is moving towards the activated electro-magneticactuator, the pull force may attract the container carrier towards theactivated electro-magnetic actuator. In a second position range when thecontainer carrier has traversed the electro-magnetic actuator, the pushforce may push the container carrier away from the activatedelectro-magnetic actuator now generating a magnetic field having anopposite polarity. Additionally, the magnetic field strength may bechanged in response to the sensed position to provide a steady movementof the container carrier. The electro-magnetic actuators may be adaptedto generate magnetic fields having only a single polarity to simplifythe system. In this case, the activated electro-magnetic actuator maygenerate the pull force in the first position range when the containercarrier is moving towards the activated electro-magnetic actuator. Inthe second position range when the container carrier has traversed theelectro-magnetic actuator the electro-magnetic actuator may bedeactivated.

For moving a first container carrier along a first transport path, afirst group of electro-magnetic actuators may be activated along thefirst transport path. For independently and at least partiallysimultaneously moving a second container carrier along a secondtransport path, a second group of multiple electro-magnetic actuatorsmay be activated along the second transport path. “Simultaneously” canindicate that during a certain time interval both the first and thesecond container carrier can move. The electro-magnetic actuators of thefirst or the second group may be activated one after the other along therespective transport path. Alternatively, two or more adjacentelectro-magnetic actuators along the respective transport path may beactivated at least partially overlapping in time.

A movement of a container carrier placed on a field on top of a firstelectro-magnetic actuator to an adjacent field on top of a secondelectro-magnetic actuator may comprise activating the first and thesecond electro-magnetic actuator and a third electro-magnetic actuatoradjacent to the first electro-magnetic actuator and opposite to thesecond electro-magnetic actuator and part of the same row or column asthe first and the second electro-magnetic actuators in a predeterminedorder.

If the container carriers comprise a first permanent magnet arranged inthe center of a stand of the container carrier and a second permanentmagnet having a ring shape arranged in the stand surrounding the firstpermanent magnet the method may further comprise activating the secondelectro-magnetic actuator such that a resulting pull-force regarding thesecond permanent magnet having a ring shape can be generated andactivating the third electro-magnetic actuator such that a resultingpush-force regarding the second permanent magnet can be generated; aftera predetermined time interval or at a predetermined position of thecontainer carrier: activating the first electro-magnetic actuator suchthat a resulting pull-force regarding the second permanent magnet can begenerated and that a resulting push-force regarding the first permanentmagnet can be generated; and after a second predetermined time intervalor at a second predetermined position of the container carrier:activating the second electro-magnetic actuator such that a resultingpull-force regarding the second permanent magnet can be generated. Amovement between adjacent electro-magnetic actuators can be done in asequence of three activation patterns regarding three adjacentelectro-magnetic actuators. This can lead to a continuous uniformmovement with a high positioning accuracy. The first and second timeinterval or the first and the second position may be determined based ona sensed position of the container carrier provided by the containercarrier sensing device.

Referring initially to FIG. 1, FIG. 1 shows a laboratory sampledistribution system 100. The laboratory sample distribution system 100can be used to distribute samples or specimens, e.g. blood samples,contained within sample containers or sample tubes 3 between differentlaboratory stations or specimen-processing instruments 22, such aspre-analytical stations, analytical stations and post-analyticalstations typically used in laboratory systems.

The laboratory sample distribution system 100 can comprise a number ofcontainer carriers or Single-Tube-Carriers 1 each can carry acorresponding sample container 3 over a transport plane 4. Multipleelectro-magnetic actuators 5 (see FIGS. 2 and 3) can be stationaryarranged below the transport plane 4. Each of the electro-magneticactuators 5 can move a container carrier 1 in operating distance of acorresponding electro-magnetic actuator 5 by applying a magnetic forceto the container carrier 1.

The depicted transport plane 4 can be divided into four quadraticsub-planes 23, the sub-planes 23 can be adjacent to one another. Thetransport plane can be covered by an optional cover profile 24, thecover profile 24 can be fluidtight and can cover gaps and mitigateheight differences between adjacent sub-planes 23. The material of thecover profile 24 can provide a low friction coefficient. The coverprofile 24 may e.g. be a glass plate or a foil of polyethylene or PTFE(poly-tetra-fluoro-ethylene).

FIG. 2 shows a schematic top view on an exemplary sub-plane 23 ofFIG. 1. The sub-plane can have a first outer face 20, a second outerface 21, a third outer face 18 and a fourth outer face 19. Along thefirst and the second outer face 20 and 21, the electro-magneticactuators 5 can be arranged in a first grid dimension g1. Along thethird and the fourth outer face 18 and 19, the electro-magneticactuators 5 can be arranged in a second grid dimension g2, whereing2=2*g1. The grid dimension g1 may e.g. be about 20 mm.

The electro-magnetic actuators 5 can be arranged in rows and columns,for example, 16 rows and 16 columns, the rows and columns having eithera first grid dimension g1 or a second grid dimension g2, whereing2=2*g1, and adjacent rows having a different grid dimension andadjacent columns having a different grid dimension. If a position orfield on the transport plane has to be accessible as a targetdestination, a corresponding electro-magnetic actuator can be providedbelow that target destination. If a specific field or area has not to beaccessible, an electro-magnetic actuator may be omitted at thatposition.

FIG. 2 depicts two exemplary container carriers each having a stand 8with a circular cross section having a diameter D that is approximately1% to 20% smaller than the larger grid dimension g2. Due to this, twocarriers moving on adjacent tracks can pass by each other withoutcollision. On the other hand, the footprint can be large enough toprovide a smooth transport without much tilting.

FIG. 3 shows detailed perspective side view of the sub-plane 23 shown inFIG. 2. As illustrated, each electro-magnetic actuator 5 can be fixed ona carrier plate 26 and can comprise a ferro-magnetic cylindrical core 5a extending basically perpendicular to the transport plane 4. A coil 5 bcan surround the ferro-magnetic cylindrical core 5 a. The coil 5 b canbe applied with an actuating current provided by a driver unit (notshown) over electrical contacts 5 c. If driven by an actuating current,each electro-magnetic actuator 5 can generate a magnetic field. Whenthis field interacts with a permanent magnet 2 (see FIG. 4) in thecontainer carrier 1, it can provide a driving force moving the containercarrier 1 along the transport plane 4. The ferro-magnetic cylindricalcore 5 a can bundle and amplify the magnetic field generated by the coil5 b.

In the most simple form, each container carrier 1 may be exposed to adriving force generated by a single activated electro-magnetic actuator5 proximate to the corresponding container carrier 1 thereby pulling thecontainer carrier 1 towards the activated electro-magnetic actuator 5.Further, it can be possible to superpose push and pull driving forces ofmultiple electro-magnetic actuators 5 proximate to the correspondingcontainer carrier 1.

Further, it can be possible to activate multiple electro-magneticactuators 5 at the same time to move multiple different containercarriers 1 independent of each other along predetermined paths over thetransport plane 4.

In order to sense the presence and position of container carriers 1located on the transport plane 4, a container carrier sensing device canbe provided. One embodiment can comprise a printed circuit board 25having multiple IR based reflection light barriers 17 arranged in a gridon top as shown in FIG. 3.

The IR based reflection light barriers 17 can detect container carriers1 placed on top of a corresponding light barrier 17 since the containercarriers 1 can be arranged to reflect IR radiation emitted by the lightbarriers 17. If no container carrier is present, no reflected IR lightcan get into the IR sensor of a corresponding light barrier 17.

FIG. 4 shows a container carrier 1 according to a first embodiment. Thecontainer carrier 1 can comprise a ball-shaped permanent magnet 2. Adistance 1 between a center of the at least one permanent magnet 2 and abottom surface 8 a of the container carrier, the bottom surface 8 a canbe in contact with the transport plane 4, can lie within a range ofabout 5 mm to about 50 mm and may be approximately 12 mm. A height h ofthe container carrier 1 may be approximately 42 mm.

The permanent magnet 2 may be made from hard ferromagnetic materials.These can include e.g. iron ore (magnetite or lodestone), cobalt andnickel, as well as the rare earth metals. A north pole N of thepermanent magnet 2 can be directed towards the transport plane.

A stand 8 of the container carrier can have a circular cross sectionhaving a diameter of approximately 3.5 cm to 4.5 cm coveringapproximately five electro-magnetic actuators 5 if positioned in thecenter of a cross formed by the five electro-magnetic actuators 5. Theelectro-magnetic actuator in the center of the cross can be fullycovered, wherein the four outer electro-magnetic actuators can be nearlycovered by half. Due to this, two carriers moving on adjacent tracks canpass by each other without collision. On the other hand, the footprintcan be large enough to provide a smooth transport without much tilting.

The container carriers may comprise a sample container fixer which maye.g. be incorporated in form of flexible flat spring 28. The flexibleflat spring 28 can be at the side wall of the cylindrical opening of thecontainer carrier 3. The flexible flat spring 28 can safely fix thesample container 3 within the container carrier 1, even if the samplecontainer 3 has a smaller diameter than the corresponding opening.

If different sample container types are used, e.g. having different formfactors, it can be even possible to provide specific container carrierswith different inner diameters corresponding to respective samplecontainer types.

FIG. 5 shows a container carrier 1′ according to a second embodimenthaving a different magnet arrangement and a correspondingelectro-magnetic actuator 5′. The container carrier 1′ can comprise afirst permanent magnet 6 arranged in the center of a stand 8 of thecontainer carrier 1′ and a second permanent magnet 7 having a ring shapearranged in the stand 8 surrounding the first permanent magnet 6. Thepermanent magnets 6 and 7 can have a reverse polarity. A north pole ofthe center permanent magnet 6 and a south pole of the ring shapedpermanent magnet 7 can be directed towards the transport plane 4.

Further, the container carrier 1′ can comprise a RFID tag 9 storing aunique ID corresponding to a specific container carrier. The RFID tag 9can comprise a ring shaped antenna 10 which can be arranged in the stand8 of the container carrier 1′ between the first and the second permanentmagnet 6 and 7.

The corresponding electro-magnetic actuator 5′ can comprises aferromagnetic core having a center finger 11 and four outer fingers 12,13, 14, and 15, each of the fingers extending perpendicular to thetransport plane 4, wherein only the center finger 11 can be surroundedby a coil 16 being driven by an actuating current Ia. This arrangementcan reduce the number of coils needed for activating theelectro-magnetic actuator 5′ compared with the embodiment shown in FIG.3, wherein the center finger 11 and the outer fingers 12 to 15 caninteract advantageously by providing push and pull forces, respectively,especially if the container carrier 1′ is arranged as shown.

FIG. 6 shows a simulated magnetic flux density B for the case that acontainer carrier as depicted in FIG. 4 is positioned on top of anelectro-magnetic actuator 5_2 not being activated and an adjacentelectro-magnetic actuator 5_3 being activated. Different flux densitiesB can be represented by corresponding hachures.

As shown, the ball shaped permanent magnet 2 in conjunction with aferromagnetic core of the non-activated electro-magnetic actuator 5_2can cause an unwanted magnetic retention force F2 pulling the permanentmagnet 2 towards the ferromagnetic core of the non-activatedelectro-magnetic actuator 5_2, thereby causing an unwantedforce-component in opposite direction of the desired movement andadditionally increasing friction between the corresponding surfaces ofthe transport plane and the stand. The activated electro-magneticactuator 5_3 can generate a force F1.

In order to reduce these unwanted effects, it can be possible togenerate an opposing magnetic field by reversely activating theelectro-magnetic actuator 5_2 pushing the container carrier, therebyreducing friction. Alternatively or additionally, it can be possible tochoose an optimized distance between the permanent magnet 2 and thetransport plane, see also the description regarding FIG. 4.Nevertheless, the magnetic forces in a desired movement direction usinga ball-shaped permanent magnet 2 can be higher compared to a bar magnet,since the resulting distances between the magnetically active sphericalsurface of the permanent magnet 2 and the active electro-magneticactuator 5_3 can be smaller.

FIG. 7 shows a side view of an embodiment of a sub-plane comprising amagnetizable coupling element 27 providing a magnetic coupling betweenadjacent electro-magnetic actuators 5. As shown, only theelectro-magnetic actuator 5_3 can be activated by driving thecorresponding coil with a driving current and can cause a magnetic flowguided by the coupling element 27 and extending in the ferromagneticcores of the non-activated electro-magnetic actuators 5_2 and 5_3. As aresult, a magnetic push force can be generated by the electro-magneticactuator 5_2 in interaction with the permanent magnet 2 reducingfriction and superimposing in the desired direction with a pull forcegenerated by the activated electro-magnetic actuators 5_3.

FIG. 8 shows a movement of a container carrier 1 and an activation orderof corresponding electro-magnetic actuators 5_1 to 5_5 according to afirst embodiment. As shown, at time t=0 only the electro-magneticactuator 5_2 can be activated such that it can generate a pull forcemoving the container carrier 1 in the shown direction.

At time t=1, the container carrier 1 has moved such that it can resideon top of the electro-magnetic actuator 5_2, what e.g. can be sensed bythe container carrier sensing device. In order to continue the movementelectro-magnetic actuator 5_2 can be deactivated and electro-magneticactuator 5_3 can be activated, thereby pulling the container carrier 1forward.

At time t=2, the container carrier 1 has moved such that it can resideon top of the electro-magnetic actuator 5_3. In order to continue themovement electro-magnetic actuator 5_3 can be deactivated andelectro-magnetic actuator 5_4 can be activated, thereby pulling thecontainer carrier 1 forward.

The above steps can be repeated as long as a movement is desired.Concluding, a group of multiple electro-magnetic actuators 5_1 to 5_5along a transport path can be sequentially activated to move thecontainer carrier 1 along the first transport path.

Since the electro-magnetic actuators 5 can be activated independently,it can be possible to independently and simultaneously move a pluralityof different container carriers 1 along different paths, whereinself-evidently collisions have to be avoided.

FIG. 9 shows a movement of a container carrier 1′ and an activationorder of corresponding electro-magnetic actuators 5_1 to 5_3 accordingto a second embodiment. FIG. 5 shows the container carrier 1′ in moredetail. In the shown embodiment, a movement of the container carrier 1′placed on a first electro-magnetic actuator 5_2 to an adjacent secondelectro-magnetic actuator 5_3 can comprise activating the first and thesecond electro-magnetic actuators 5_2 and 5_3 and a thirdelectro-magnetic actuator 5_1 adjacent to the first electro-magneticactuator 5_2 in a specific order and polarity. The electro-magneticactuators 5_1 to 5_3 can be part of the same row or column and can beactivated generating a south-pole (S) or a north-pole (N) pointingtowards the container carrier 1′.

In a first step, at t=0, the second electro-magnetic actuator 5_3 can beactivated such that a resulting pull-force regarding the secondpermanent magnet 7 having a ring shape can be generated and the thirdelectro-magnetic actuator 5_1 can be activated such that a resultingpush-force regarding the second permanent magnet 7 can be generated.

After the container carrier 1′ reaches a first predetermined position attime t=1, what e.g. can be sensed by the container carrier sensingdevice, the second and third electro-magnetic actuators 5_1 and 5_3 canbe deactivated and the first electro-magnetic actuator 5_2 can beactivated such that a resulting pull-force regarding the secondpermanent magnet 7 can be generated and that a resulting push-forceregarding the first permanent magnet 6 can be generated.

After the container carrier 1′ reaches a second predetermined positionat time t=2, the first and the third electro-magnetic actuators 5_1 and5_2 can be deactivated and the second electro-magnetic actuator 5_3 canbe activated such that a resulting pull-force regarding the secondpermanent magnet 7 can be generated.

In one embodiment, a movement between adjacent electro-magneticactuators 5_2 and 5_3 can be performed in a sequence of three activationpatterns regarding three adjacent electro-magnetic actuators 5_1 to 5_3.This can lead to a continuous uniform smooth movement with a highpositioning accuracy.

FIG. 10 shows a further embodiment of a sub-plane 23′. According to thisembodiment, the electro-magnetic actuators 5 can be arranged in rows andcolumns forming a grid having a single grid dimension g3. The distancebetween adjacent or consecutive electro-magnetic actuators 5 in each rowand each column can be g3.

FIG. 10 depicts two exemplary container carriers each having a stand 8with a circular cross section having a diameter D that can beapproximately 1% to 20% smaller than the grid dimension g3. Due to this,two carriers moving on adjacent tracks can pass by each other withoutcollision. On the other hand, the footprint can be large enough toprovide a smooth transport without much tilting.

Having described the present disclosure in detail and by reference tospecific embodiments thereof, it will be apparent that modifications andvariations are possible without departing from the scope of thedisclosure defined in the appended claims. More specifically, althoughsome aspects of the present disclosure are identified herein aspreferred or particularly advantageous, it is contemplated that thepresent disclosure is not necessarily limited to these preferred aspectsof the disclosure.

We claim:
 1. A laboratory sample distribution system, the systemcomprising: a plurality of container carriers, wherein each containercarrier comprises one magnetically active device and carries a samplecontainer; a transport plane to carry the container carriers; and aplurality of electro-magnetic actuators stationary arranged below thetransport plane, wherein the electro-magnetic actuators move a containercarrier on top of the transport plane by applying a magnetic force tothe container carrier, wherein the plurality of electro-magneticactuators is arranged in rows and columns forming a grid, whereinadjacent rows and adjacent columns have different grid dimensionsselected either from a first grid dimension (g1) or a second griddimension (g2), wherein the grid dimensions specify a distance betweenadjacent electro-magnetic actuators in a given row or column, whereinthe second grid dimension (g2) is larger than the first grid dimension(g1), and wherein the container carriers each have a stand, wherein thestand has a circular cross section having a diameter (D) that is equalto or less than the larger grid dimension.
 2. The system according toclaim 1, wherein the transport plane is formed by multiple adjacentsub-planes.
 3. The system according to claim 2, further comprising, acover profile covering the sub-planes.
 4. The system according to claim3, wherein the cover profile covers gaps and mitigates heightdifferences between adjacent sub-planes.
 5. The system according toclaim 3, wherein the cover profile is fluidtight.
 6. The systemaccording to claim 3, wherein the cover profile is glued to the topsurface of the sub-planes.
 7. The system according to claim 3, whereinthe cover profile comprises a glass plate, a non-magnetic metal plate, afoil of plastic material, or combinations thereof.
 8. The system ofaccording to claim 7, wherein the non-magnetic metal plate is analuminum plate.
 9. The system of according to claim 7, wherein the foilof plastic material is a foil of polyethylene or PTFE(poly-tetra-fluoro-ethylene).
 10. The system according to claim 3,wherein a bottom surface of the container carriers and the surface ofthe cover profile are arranged to reduce friction between the surfaces.11. The system according to claim 2, wherein each sub-plane has a firstouter face, a second outer face, a third outer face and a fourth outerface, wherein along the first and the second outer face theelectro-magnetic actuators are arranged in a first grid dimension g1 andalong the third and the fourth outer face the electro-magnetic actuatorsare arranged in a second grid dimension g2, wherein g2=2*gl.
 12. Thesystem according to claim 1, wherein the plurality of electro-magneticactuators are arranged in rows and columns forming a grid having a griddimension (g3).
 13. The system according to claim 12, wherein thecontainer carriers each have a stand, wherein the stand has a circularcross section having a diameter (D) that is equal to or less than thegrid dimension (g3).
 14. The system according to claim 1, wherein thecontainer carriers each have a stand, wherein the stand has a circularcross section covering five electro-magnetic actuators if positioned inthe center of a cross formed by five electro-magnetic actuators.
 15. Thesystem according to claim 14, wherein the electro-magnetic actuator inthe center of the cross is fully covered, wherein the four outerelectro-magnetic actuators are covered by half if the stand ispositioned in the center of the cross formed by the fiveelectro-magnetic actuators.
 16. The system according to claim 14,wherein the stand has a diameter in the range of 3.5 cm to 4.5 cm. 17.The system according to claim 1, wherein each electro-magnetic actuatorcomprises a ferromagnetic core, wherein the ferromagnetic core causes aholding force acting on the at least one magnetically active device ofthe container carrier placed on top of the electro-magnetic actuator ifthe electro-magnetic actuator is not driven by an actuating current. 18.The system according to claim 1, wherein the at least one magneticallyactive devices is a permanent magnet.
 19. The system according to claim18, wherein the permanent magnet is ball-shaped.
 20. The systemaccording to claim 1, wherein each container carrier comprises a firstpermanent magnet arranged in the center of a stand of the containercarrier and a second permanent magnet having a ring shape arranged inthe stand surrounding the first permanent magnet, wherein the first andsecond permanent magnets have a reverse polarity and the ring shapedsecond permanent magnet comprises a circular area having a diameter thatis less than a distance between axes of adjacent electro-magneticactuators.
 21. The system according to claim 1, wherein each containercarrier comprises a RFID tag storing a unique ID corresponding to aspecific container carrier.
 22. The system according to claim 1, whereineach electro-magnetic actuator comprises a ferromagnetic core having acenter finger and four outer fingers, wherein each finger extendsperpendicular to the transport plane.
 23. The system according to claim1, further comprising, a container carrier sensing device to sense thepresence and/or position of container carriers located on the transportplane.
 24. The system according to claim 1, further comprising, amagnetizable coupling element to provide a magnetic coupling betweenadjacent electro-magnetic actuators.
 25. The system according to claim1, further comprising, a security cover to cover the transport plane andthe container carriers placed on the transport plane.
 26. The systemaccording to claim 25, wherein the security cover has an open state anda closed state, wherein in the open state, the transport plane is atleast partially accessible by a user and in the closed state, thetransport plane is not accessible by a user.
 27. A method of operating alaboratory sample distribution system according to claim 1, the methodcomprising: activating at least one of the electro-magnetic actuators toapply a magnetic force to a container carrier within an operatingdistance of the at least one activated electro-magnetic actuator. 28.The method according to claim 27, further comprising, activating the atleast one electro-magnetic actuator in response to a sensed position ofthe container carrier to be applied with the magnetic force.
 29. Themethod according to claim 27, further comprising, activating a firstgroup of multiple electro-magnetic actuators along a first predeterminedtransport path to move a corresponding first container carrier along thefirst transport path.
 30. The method according to claim 29, furthercomprising, independently and at least partially simultaneously to theactivating of the first group of multiple electro-magnetic actuatorsactivating a second group of multiple electro-magnetic actuators along asecond predetermined transport path to move a corresponding secondcontainer carrier along the second transport path.